A. You are detoxing however many years of smoking out of your body. You WILL feel like krap, your lungs WILL clear all that junk and gunk out of them and begin the healing process. Your body WILL begin filtering all those toxic chemicals out of your system. You have, after all, quit smoking for all intents and purposes. Don't be alarmed if you break out with some pimples, too !
B. You are prolly dehydrated. Most people are, even healthy ones. Both the PG and VG are "humectants" which means it's a substance that can absord liquid from a moist environment. Drink TONS of fluids, preferably water. I couldn't stand the taste of plain water, so I have a 32oz bottle and I buy those crystal light packets. Perfect! In the early days, I would slurp down 3-4 a day. Now, I am holding at 2 and feel good.
C. You might be allergic to PG. Many people are sensitive to PG (Propylene Glycol), in fact, we have a lady we work with that is terribly allergic to it! She doesn't smoke or vape, but will get the sneezies if one of our vapers gets a liquid with pg in it. Go figure.
So, you have a few things to look at. Mix and match, and hang in there

Oh, and seeing your doc isn't such a bad idea, either!